N140

I've got some I've been testing in 6 BRA. Shot a ladder at 69 F a couple weeks ago, and 31.6 gr got me 2933 +/- 5 fps with 105 hybrids. Today at 34 F the same load was 2915 fps, so 0.51 fps/deg F.

For comparison, 31.5 gr Varget was 2920 fps at 69 F, and 2885 fps at 34 F, so 1.0 fps/deg F.
I'm not understanding why the varget was worse?
 
I was surprised too. I only shot four of the N140 (Lab Radar only caught two), then I shot the Varget right after.

But, here were the Varget velocities in order:
2879, 2889, 2894, 2901, 2906, 2909

Definitely speeding up, but I figured I was shooting too fast and heating up the barrel so I averaged the first two as I figure those are best representative of the 34 degree velocity.
 
I was surprised too. I only shot four of the N140 (Lab Radar only caught two), then I shot the Varget right after.

But, here were the Varget velocities in order:
2879, 2889, 2894, 2901, 2906, 2909

Definitely speeding up, but I figured I was shooting too fast and heating up the barrel so I averaged the first two as I figure those are best representative of the 34 degree velocity.
That's even more interesting that it just speeding up. What barrel are you using?